Engineering :: Heat Transfer
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1. |
Select the only wrong statement. |
A. |
heat can be converted into work |
B. |
heat can be reflected by a mirror |
C. |
heat waves cannot pass through vacuum |
D. |
heat is a form of energy |
Answer: Option C
Explanation:
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2. |
Which of the following is a form of energy? |
A. |
pressure |
B. |
momentum |
C. |
light |
D. |
power |
Answer: Option C
Explanation:
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3. |
When heats is transferred by a chain of molecules from the hot area of an object to a colder area the process of heat transfer is called |
A. |
natural convection |
B. |
forced convection |
C. |
conduction |
D. |
radiation |
Answer: Option C
Explanation:
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4. |
Heat transfer by conduction is described to |
A. |
Fouriers law |
B. |
Newtons law of cooling |
C. |
Stefan Boltzmann law |
D. |
Ficks law |
Answer: Option A
Explanation:
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5. |
Heat transfer by conduction is directly proportional to |
A. |
(thermal potential difference)/(thermal resistance) |
B. |
(thermal resistance)/(thermal potential difference) |
C. |
(thermal potential difference)(thermal resistance) |
D. |
thermal resistance |
Answer: Option A
Explanation:
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6. |
Whenever there is a temperature difference |
A. |
heat will be transferred from hotter object to colder object |
B. |
heat will be transferred from colder object to hotter object |
C. |
heat will not be transferred |
D. |
none of these answers |
Answer: Option A
Explanation:
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7. |
The units of thermal conductivity in SI unit are |
A. |
W/(m.K) |
B. |
J/(m.K) |
C. |
W/(m2.K) |
D. |
J/(m2.K) |
Answer: Option A
Explanation:
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8. |
The thermal conductivity of a gas |
A. |
decreases with increasing temperature |
B. |
increases with increasing temperature |
C. |
is independent of temperature and pressure |
D. |
is greater than the thermal conductivity of water at the same temperature |
Answer: Option C
Explanation:
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9. |
The thermal conductivity of water |
A. |
remains unaffected with change in temperature |
B. |
decreases with increase in temperature upto about 300?F |
C. |
increases with increase in temperature upto about 300?F |
D. |
is less than the thermal conductivity of air at the same temperature |
Answer: Option C
Explanation:
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10. |
If ks kl and kg are the thermal conductivities of aluminium water and air at the same temperature then |
A. |
ks > kl > kg |
B. |
kg > kl > ks |
C. |
ks > kg > kl |
D. |
kl > ks > kg |
Answer: Option A
Explanation:
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